The objective of this research is to apply the technique of fast atom bombardment mass spectrometry (FABMS) to problems involving the structure elucidation of synthetic and naturally occurring antitumor agents, metabolites of antitumor agents and complexes formed between antitumor agents and oligodeoxynucleotides. A unique approach to expanding the selection of solvents available for use as the FAB matrix will be the use of a heatable/coolable probe. Also unique will be the application of FABMS to the analysis of intact linear and cross-linked drug-oligonucleotide adducts. Mass spectral structure-fragmentation relationships will be developed for those compound classes not previously studied or studied to only a limited extent. The structure of naturally occurring antitumor agents and metabolites of clinically important anticancer drugs will be tentatively assigned on the basis of high resolution mass measurements, metastable on studies and the structure-fragmentation relationships developed in the course of these studies. The projects described in this proposal will be performed in collaboration with other medicinal and pharmaceutrical chemists involved in the design, synthesis and formulation of antineoplastic agents. The use of mass spectrometry in solving structural problems could, therefore, be of fundamental importance in development of new antitumoragents or in increasing the clinical efficacy of drugs currently being used clinically. Mass spectral analysis of the compound classes to be examined, e.g., analogs of mitomycin C, streptonigrin, mitoxantrone, will, in general require the use of FAB. Electron impact (EI) and chemical ionization (CI) will also be used in the natural product and metabolite identification studies. Desorption chimical ionization (DCI) will be examined as an alternative to FAB in the case of mitoxantrone analogs, if necessary.